1.Field of the Invention
This invention relates generally to a method and apparatus for testing a wire drawing die to determine the percent wire elongation provided thereby.
2.Description of the Prior Art
In the drawing of wire from rod stock, a succession of wire drawing dies are employed with the diameter of the wire being progressively reduced by each successive die. When the diameter of wire is reduced by drawing through a die, the length of the wire is consequently increased and in the drawing of wire through a succession of dies, it is desirable to obtain substantially the same percentage of elongation at each successive die in order to reduce the drawing force required on the wire and wear on the capstans in the drawing apparatus, and also to increase die life and drawing speed. In the past, in order to test a given wire drawing die to determine the percentage of wire elongation provided thereby, a known length of wire has been manually pulled through the die and then measured to determine the elongation from which the percentage of elongation may be calculated.
It is therefore desirable to provide a method and apparatus for automatically testing a wire drawing die which provides a direct read-out of the percentage of wire elongation provided thereby.